A sweet fragrance drifts in the hot afternoon air. The scent comes from pale yellow flowers set against tough, stubby evergreen leaves.
This is Stansbury’s Cliff-Rose (Purshia stansburyana), a true rose in the family Rosaceae and a common native plant through the desert lands of Arizona, Utah, Colorado, New Mexico, Nevada, southern California, and northern Mexico. This plant grows as a shrub or small tree, usually 1 – 6 feet (0.3 – 1.8 m) tall. Reports of plants nearly 70 years old have been made, but they are more likely to live up to 40 years. During the long life of Stansbury’s Cliff-Rose, it provides an important source of browse for domestic cattle and sheep, as well as mule deer, elk, pronghorn, desert bighorn sheep, and many bird species. Rodents feed on the seeds. Native peoples have made good use of the plant as well: the inner bark was made into ropes, clothing, sandals, and baskets; the wood was rendered into arrow shafts; and the leaves were medicinally used as both an emetic and a wound wash. Modern pharmaceutical studies seem to indicate that triterpenoids extracted from the plant might have some inhibitory effects on viruses such as HIV and Epstein-Barr (which causes mono and is associated with specific forms of cancer).
Members of the genus Purshia form a large species complex capable of easy cross-fertilization and hybridization. This tendency towards hybridization has raised some conservation concerns that the ubiquitous P. stansburyana will swamp out rarer species, especially with the breakdown of natural ecological barriers through climate change and road construction. Despite these concerns, Stansbury’s Cliff-Rose continues to define the landscape of the high desert cliffs and rocky hillsides, providing food and shelter for wildlife and fixing nitrogen in the soil. The plant is recommended for seeding in areas in need of habitat restoration from disruptive human activities such as mining.
P. stansburyana was named for Captain Howard Stansbury (1806 – 1863) of the Corps of Topographical Engineers of the U.S. Army, who led a surveying expedition to the Great Salt Lake in 1849 – 1850. His party brought back specimens that were later described and named by New York botanist John Torrey (1796 – 1873). In handing over the collected plants, Stansbury had to make apologies to Torrey due to the sudden disappearence of the expedition’s naturalist, who “. . . .being violently attacked with the California fever, unceremoniously abandoned his post and walked off to the mines, leaving me to shift for myself. Consequently the collection was made by persons but little acquainted with botany, and I fear you will not find it of any great value (quoted from Tiehm 1987).” Stansbury seems to have lost a number of men to the new California gold rush, but the expedition was a major success and Stansbury remains honored in the name of this lovely desert rose.
Baggs, Joanne E. & J. Maschinski. 2000. “The Threat of Increasing Hybridization of an Endangered Plant Species, Purshia subintegrata, in the Verde Valley, Arizona.” Southwestern Rare and Endangered Plants: Proceedings of the Third Conference. PP. 25 – 28.
Howard, Janet L. 1995. “Purshia mexicana var. stansburiana.” Fire Effects Information System. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Library. Accessed 29 June 2016.
Pendleton, R.L. & E.D. McArthur. 1995. “Reproductive Biology of Bitterbrush: Interaccessional Hybridization of Plants Grown in a Common Garden.” Proceedings — Ecology and management of annual rangelands. General Technical Report INT-GTR-313, USDA Forest Service, Intermountain Research Station, Ogden, UT. Pp. 266 – 270.
Stubbendieck, James, Stephan L. Hatch, & L.M. Landholt. 2003. North American Wildland Plants: A Field Guide. Lincoln, NE: University of Nebraska Press.
Tiehm, Arnold. 1987. “Index to Plants Collected on Howard Stansbury’s Expedition to the Great Salt Lake, 1849 – 1850.” Brittonia 39 (1): 86 – 95.